Engine rattle/knock

[Soleman20]

I have a 1994 G20t and the engine rattels/knocks when I start it. It only lasts for 2 seconds and it does not do it on the 1st start of the day, only after it has been started once and sits for 3-4 hrs. If the car sits for 30 min. or an hour, it will not do it. I am positive it is a noise internally in the engine. I asked a mechanic and he said it is not a problem because it only lasts a second or 2. He also said that the lifters are not adjustable on a G20 so its not that. He said he puts a teflon additive in Mazdas that have a knocking problem and it goes away immediately. I am thinking it is the valves, or the cams, or the timing chain/gears. Anyone have any clues or is familiar with this problem?

[NismoPC]

Check www.se-r.net. There is a ton of info there regarding timing chain start up chatter and replacement of the timing chain tensioner.

Start here then click on the links within the remarks.

http://www.se-r.net/car_info/problem...ne%20noises%20(clatter)

Good luck!:smoker2:

[P10DET]

Originally posted by Soleman20
I have a 1994 G20t and the engine rattels/knocks when I start it. It only lasts for 2 seconds and it does not do it on the 1st start of the day, only after it has been started once and sits for 3-4 hrs. If the car sits for 30 min. or an hour, it will not do it. I am positive it is a noise internally in the engine. I asked a mechanic and he said it is not a problem because it only lasts a second or 2. He also said that the lifters are not adjustable on a G20 so its not that. He said he puts a teflon additive in Mazdas that have a knocking problem and it goes away immediately. I am thinking it is the valves, or the cams, or the timing chain/gears. Anyone have any clues or is familiar with this problem?

Well, it actually is the "lifters." Start-up clatter is caused by leak-down of the hydraulic valve lash adjusters (HVLA), which is what your mechanic is calling lifters. He is correct that they are not adjustable. Do not put that Teflon crap in your engine. It won't do any good what so ever.

My personal theory is that the leak-down is due to leaking past the seals in the chain tensioner. It's a total crap shoot trying to get rid of it.

[GtRider]

iam starting to get that same problem!
does anyone know about how much would this job cost to do?